Remove modeline before creating file parser

This makes NEWS and other files look good.  This also deletes the
modeline from ruby files, but this should be harmless as those parsers
don't currently care about the modeline.

Fixes #178

Author: drbrain

History.rdoc

@@ -18,6 +18,8 @@
   * RDoc no longer attempts to parse binary files.  Bug #189 by postmodern,
     Bug #190 by Christoffer Lervåg, Bug #195 by Aaron Patterson
   * `rdoc --pipe` output now contains <code></code> for markdown compliance.
+  * RDoc no longer leaves emacs-style modelines in .txt, .md or .rd files.
+    Bug #178 by Zachary Scott
 
 === 4.0.0 / 2013-02-24
 

lib/rdoc/parser.rb

@@ -218,6 +218,8 @@ def self.for top_level, file_name, content, options, stats
 
     return unless parser
 
+    content = remove_modeline content
+
     parser.new top_level, file_name, content, options, stats
   rescue SystemCallError
     nil
@@ -232,6 +234,13 @@ def self.parse_files_matching(regexp)
     RDoc::Parser.parsers.unshift [regexp, self]
   end
 
+  ##
+  # Removes an emacs-style modeline from the first line of the document
+
+  def self.remove_modeline content
+    content.sub(/\A.*-\*-\s*(.*?\S)\s*-\*-.*\r?\n/, '')
+  end
+
   ##
   # If there is a <tt>markup: parser_name</tt> comment at the front of the
   # file, use it to determine the parser.  For example:

test/test_rdoc_parser.rb

@@ -110,6 +110,21 @@ def test_class_for_forbidden
     end
   end
 
+  def test_class_for_modeline
+    temp_dir do
+      content = "# -*- rdoc -*-\n= NEWS\n"
+
+      open 'NEWS', 'w' do |io| io.write content end
+      app = @store.add_file 'NEWS'
+
+      parser = @RP.for app, 'NEWS', content, @options, :stats
+
+      assert_kind_of RDoc::Parser::Simple, parser
+
+      assert_equal "= NEWS\n", parser.content
+    end
+  end
+
   def test_can_parse_modeline
     readme_ext = File.join Dir.tmpdir, "README.EXT.#{$$}"